1980 450sl low miles.first start of the day.When moving off I get what sounds something like a pinging noise.Will not make the noise if not moving and just reving engine a little.Noise goes away in a few minutes.HELP.Thanks Michael

Steve thank you so much.You are the first to attempt a solution to my problem.I will check it out.The reason for the title and repost.Was to generate interest.This site is so popular,some questions get buryed.Thanks again Michael

But seriously, I really wasn't trying to be a, uh, how you say, proprio uno stronzo? Si. I just wanted to suggest that perhaps you needed to let it warm up a little longer and see if the sound went away. Besides, ANY response keeps your posting on page one!

I think that Steve may be on to something aside from the Yiddish spelling of shroud.

Dear Kuan Thank you for you reply.I do not know how to be more difinative about the noise.I do not think it is an engine noise.I think it is one of the many smog devices going spastic.If I let the car sit and run for awile I get to noise.And I have no noise when driving.Only the first time of the day when I start to drive off.

I agree with the exhaust leak possibility. This a problem I've seen on many different cars, not just Mercedes. Look for black powder around the mating surfaces. The fan shroud idea is also worth a quick look. Power braking the engine with the hood raised might tell you all you need to know. Other than that I can only think of things like CV joints, or loose driveshaft disc bolts, but I think those would be there at all times. It sounds like temperature is the key, and that makes the exhaust leak my bet. Good Luck! Lets us all know what you find.

Well, if it is indeed an exhaust leak, you should almost be able to hear each individual "tick" (if you will). If it were pinging, I doubt that if would be confined to just one cylinder, and therefor sound more like chains rattling rather rapidly. Right?
The reason that you wouldn't be able to hear it at plain ole idle, is that there isn't much combustion to speak of, going on at that moment...once you step on the gas though, you instantly increase the volume of gasses wanting to take the shortest route to freedom.
So far the exhaust leak sounds like the most plausible explanation for da noise.
-Larry

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Could it simply be the lifters ticking before they are fully pressurized with oil? "Pinging" generally refers to detonation under load, not something you would hear at start up. Is it more like a light metallic rattle? I have seen changing to the OE manufacturers oil filter cure this. Sometimes the cheapies allow oil to drain back that a premium filter holds allowing quicker pressure upon start up. At any rate a brief rattle at start up on a 20 yr old car shouldn't worry you too much. Good Luck

Rocket and you others who thought it may be an exaust leak.To me that sounds great I am going to check it out as soon as I can.When I do find the problem I will make sure to let everyone know.Thanks again Michael

I started it up this morning moved off and everytime i patted the pedal a little I got the noise.After listing to it this morning.It seems to sound more like a light knock than ping.Thanks in advance Michael.